Our long-term objectives on this project are to explore the molecular bases of membrane structure and function, with emphasis on the application of such information to problems of immunology, hematology, and lymphocyte biology. We propose to carry out the following specific studies: 1. to study the mechanism for unexpected finding that erythrocyte membranes exclude lipid-soluble drugs; 2. to explore possible molecular structural relationships among differnt myosins and erythrocyte spectrin components, by immunochemical and peptide fragmentation studies; 3. to investigate the possible capping and co-capping of recognition molecules in specific cell-cell interactions, as predicted by a scheme fro such interactions which we have recently proposed; 4. to explore by immunochemical and immunocytological techniques, what happens to the nuclear membrane as it disintegrates and subsequently reforms through the mitotic phase of the cycle.